I find this a problematic question to ask because it’s all hypothetical. Your answer reveals more about you than it does about Jesus.

Would Jesus have cried?  Of course, unless you consider crying to be sin.

Would Jesus have fussed during a diaper change? Well, other than the fact that diapers weren’t the same issue they are then, of course–unless you consider fussing during a diaper change to be a sin.

Would Jesus have done something Mary told him not to?  As a toddler? Of course, unless you consider being a normal toddler and doing normal toddler things sin.  I don’t happen to.  Which is part of why I don’t take a whole lot of offense when my toddlers do toddler things.

I can see not realizing how universal different behaviors are when you are parenting your first toddler.  I understand getting worried about the future spiritual state of your first toddler.  I’ve got numbers 4 and 5 in the 3yo stage and so far we haven’t run into anything new   Considering they are also sweetly sing the Shabbat blessings and my older children profess faith I’m really not going to stress about fussing over wanting their vitamins now, no now, no NOW!  It’s not SIN.

I find it very helpful to ask the question . . . does God really care about this specific behavior?  He cares intimately about my children; he cares intimately about how they are developing in the areas of empathy and love and compassion and accountability–are they being trained in the Torah?  THAT he cares about! But are they fussing over who gets their diaper changed first?  I think he looks on and smiles–perhaps he remembers his time at that age and looks on with a knowing glance.

See, Jesus was perfect. And Jesus was FULLY HUMAN.  If he weren’t, he could not have been the perfect sacrifice that he was.  I’m very fine with a toddler Jesus who was a normal child doing normal child things at the appropriate ages and stages.  Considering those things develop the mind-body connection and serve a purpose–you betcha I’m comfortable with a Jesus who developed perfectly!